Packing ring



Jan. 20. 1925.

L. G. soN

PACKING RING l Original AFiled Ot. 2, -1915 f Pil' gv fyi?.

,4 TTORNEV Patented Jan. 20, l1925.

UNITED- STATES LARS GUSTAF NILSON, 0F HO'BOKEN. NEW JERSEY.

PACKING einer.-

Applicatonled October 2,-1915, Serial No. 53,768. Renewed April 9, 1920. Serial No. 372,703.

To all whom t may concern:

Be it known that I, LAns GUs'rAr NILsoN, a citizen of the United States, and a resident of Hoboken, in the county of Hudson and State of New Jersey, have invented certain new and useful Improvements in Packing Rings, of which the following is a specification.

This invention relates particularly to i packing rings made from metal, such `as are A further object is the production of a` packing ring that will at all times, and along its entire circumference, exert an even, yielding pressure upon the walls of the cylinder, barrel, or other part with which it coacts.

Another object is the provision of a. packing ring of uniform cross-section, capable of being applied to a piston so as to leave the same space all around its own circumference and the bottom of the piston groove wherein it is lodged, and sol that the ends of the ring will be maintained in alignment` one with the other, irrespective of the eX- pansion and contraction to which they are normally subjected.

Still another object is to provide a packing ring that is easily adjusted in position, and of such simple construction. as to be amenable to rapid manufacturing methods, which will make it a low-cost appliance.

Other objects. and advantages of the invention will become apparent as the specification proceeds.

With the vaforesaid objects in View, the invent-ion consists of the improved construction, arrangements and combinations of parts hereinafter described pointed out in the subjoinedclaims, and illustrated in their preferred embodiment by the accompanying drawings, wherein Figure ,1 is a plan view of this improved at the ends; and

packing ring applied to a. piston, adjacent parts being shown in section:

Figure 2`is an edge or side View of the ring represented -in Fig. l, adjacent parts being again shown in section;

Figure 3 is a section on the line 3-3 of Fig. 2, looking in the direction of the ar- .bend more than the body of the ring, so

that they ywill iit a circular bore when sprung together;

3rd. Rings of either one of the two tvp/es n n just mentioned, furnished with loose pieces interposed between the ends of the rings or placed under the open gaps thereof;

4th. Multiple and double rings placed concentrically one within the other, and arranged to clasp each other so as to make or break joints, which are staggered;

th. Rings formed with single or double lips, intended to lap over the joint or spline 6th.v Rings hammered or compressed circumferentially in order to impart to them the required resilience,

Experience has shown that a ring of the first form above referred to bears onlyat the ends and inthe middle.

A ring of variable thickness, or eccentric, as stated with reference to the 2nd form, exerts an unequal pressure- Ithat results in uueven, detriment-al wear of the cylinder walls, and besides, .a pocket is formed inside the thinner portion of the ring, which, in the case of internal combustion engines particularly, soon fills up with soot that injuriously affects the resilience of the ring.

According to the 3rd form, the loose or eXtra piece added to the ring is supposed to till .up the interstices between the ends thereof, but in practice the ring does not eX- which bakes them together, so to say, in one solid mass and renders the parts inoperative.

The species of ring alluded to as the 5th form is diliicult and expensive to produce. in a manufacturing sense, and frequently it becon'ies inelastic at the joint.v

lVhile the ring appertaining to the (Sth .form has given fairly good results. the

manufacture thereof involves an indirect j method of producing the saine.

A metallic packing rin'g especially suited for the cylinders and pistons of internal combustion engines and obviating the deticiences hereinbefore outlined, is realized by following the design and method of procedure embodiedl in the present invention.

Generally described, the invention comprises a ring formed by preference from an annular shell or blank of even thickness `throughout, the sides whereof are machined in such a Way that after a piece of the metal has been cut out of the severed ring to produce a gap between the ends thereof, these sides, when subjected to a uniform strain or load stress, Will curve sufficiently for the ring to fit at once the cylinder into which it is sprung, with the same pressure all around. Further the invention includes a slip or leather iexibly joining the aligned ends of A the ring and also'preventing leakage at their juncture.

It is a known fact that a beam of uniform cross-section throughout, and held horizontally by one end only, will, if evenly loaded in the direction of its length. detiect according to a parabolic curve, also, it is true, that a beam of this desigiiation. when given an initial set conforming to a para! bolic curve, will, if loaded in a similar manner. deliectto a straight line. Applying this principle to the present invention, and refering particularly to Fig. 4 of the (lrawing, it will be noted that if a split ring or annulus,

as 10. of even cross section, is uniformly loaded internally in both directions from a point 11. opposite the split or cut 12, the sides and ends 13 ofthe rinfr Will spread apart and out on curves, as indicated by the dotted lines 14. The curved sides and ends bear the same relation to the original annulus as a parabolic curve does to the straight line,- in the manner before described with reference to a beam in loaded and unloaded conditions. Similarly if a strip, formed initially curved along the dottedlines let, 14, is loaded evenly, it willinversely revert to the condition represented by the full lines ,13. To accomplish these results, in pursuance of the invention. an annulus ofthe size indi-` cated by the dotted lines 14 is machined in such a way that; after cutting otll a short piece as 15 therefrom and subjectingthe parted sides to a load strain, to wit, by pressing them evenly all around, these sides will take the curvature' denoted by the full lines 13, 13. The machining is preferably performed by imparting either to the tool or to the Work a slight reciprocatory or swinging motion, Which Will produce the correct swelled-out ell'ect indicated at tt. t4, on each side of lthe cuttingl point l2. 'l` he location of the latter is prctletcrmincd by tbe same tool, by feeding it in abruptly at. the chosen point, to produce a depression as at 1G.

',l`hc extent of the curvature which in the present s-pecilication and claims is called c vclioparalmlic, or any particular size of ring is figured ont in advance according to a predetermined shape calculated on definite.

transferringI distances from similarly located points in a loaded beam as above referred to. It is important to note in this connection that permanentbv good results can be obtained only by using materials haring natural resilience or elasticity.

rl`he ends of the tinishcdring,T are preferably formed with tongues, 1T. ttl. offset in opposite directions so as to lap one over the other. As shown in Figs. l. 2 and is', the tongue 17 takes up one-half `the depth of the ring at one of its ends. and the tongue 1S occupies the remaining half of the rings depth at the other end thereof. Terminal spaces 19, 2O are provid-ed in the ring foi the ends of the tongues 17. 18 respectively,

to afford them freedom of motion when the ring is compressed.

An elastic slip or feather 25 is provided in order to block up the said spaces 19, 20, so as to prevent the charge in the cylinder from escaping through them, or between the coutacting faces of the tongues 17, 18. This slip is confined mostly in grooves or kerfs, as 26, extending inwardly from both ends of the split ring, in a circumferential direction, and preferably. concentric with the'ring-"s axis. One end of the slip is also preferably anchored Within its groove. while the other end thereof is left free to move in the opposite groove.. In the present exeinplitication of theinvention. they said slip 25 extends side- Wise for the full depth ol the ring, and is formed at one end with a slight corrugation 2T, which upon being forced into the oppoends of the ring in alignment, without intertering with the normal pressure outward or inward at the point of juncture.

Although an outwardly-expaiiding onepiece packing ring'lias been shown and described, it is understoodvthat the invention contemplates aswell a ring composed of plural parts, and also an inwardly-clasping ring, embodying the featureslierein recited.

Having described my invention, what I desire to secure by Letters Patent and claim is:-

l. A packing ring` consisting of a parted annulus provided with terminal slits, and a bridging element fitted therewitliin, said element having an uneven surface adapted to engage one of said slits and be bounc therein by lateral compression.

2. A packing ring consisting of a parted vannulus formed with slits in its opposite ends, and a bridgingelement therefor having a corrugation whereby it can releasably engage one of said slits.

3. A split packing ring having a circular contour when compressed to Working size, and having when free the form of a noncircular ring Whosecurvature constitutes minals of radii vectors taken from a. common center and progressively increasing in length as they approach the free ends of the ring, the initial radius vector being drawn normal to the outer curve of the ring and being equal in lengthV to the radius of the circular bore for which said ring is intended.

5. A split packing ring for a circular bore, which packing ring when free has the form of a curve constituting a. cyclic parabola and bearing the same relation to the circle of the bore when the ring is compressed as the parabola of a beam loaded at one end bears to the unloaded beam.

6. A s lit acking ring for a circular bore, sai pac (ing ring being of uniform cross-section through-out and having when free the form of a curve external of its contour when compressed, the curve of -said ring when free constituting a cyclic parabola and bearing the same relation to the circle of't-he bore as the parabola of a beam loaded at one end bears to the'unloaded beam.

7. A resilient split packing ring for a circular bore having when free the form of a curve external. of its curvature when compressed, said curvature of the ring whenV free, constituting a cyclic parabola and bearing the same relation to the curvature of said ring when compressed to the bore as the parabola of a beam loaded at one end bears to the unloaded beam.

8. A' split packing ring of resilient material and uniform cross section, having when unlexed, the form of a normally circular split ring of the same material and cross section expanded by uniform internal pressure.

9. A split packing ring of resilient ma'- I pressure equal per unit area to the desired pressure of the packing ring against the cylinder bore.

10. A split packing ring of resilient mate? rial and uniform cross section, having, when funilexed, an external contour in the form of a curve externally tangent to a circle, the

tangent point being opposite the split portion, and the radialdistance from any givenpoint on said circle to said curve onv either side of said tangent point being equal to the deflection of a corresponding point of a centrally supported uniformly loaded horizontal beam of uniform cross section, the ends being suiiciently separated to permit the ring being flexed into thecontour of the tangent circle.

11. A split packing ring of uniform cross section, having, when unflexed, an external contour in the form of a curve externally tangent to a circle, the tangent point being opposite the split portion, and the radial distance from said circle to said curve on either side of said tangent point increasing directly as the square of the arc included between said tangent point and the measuring radius, the material of said ring being lsufficiently resilient and the endsbeing suffi form of a normally circular split ring of resilient material and uniform cross section expanded by uniform internal pressure, said blank being continuous across the portion corresponding to the' gap between the parted ends of the split ring.

14. A blank for a packing ring, the outer curvature of said blank being defined bythe in the county-oi" New York and Stute of outer terminals of radii vectors taken from New York, this lst day of October, A. D. a common center and'progressively increas- 1915.

ing in r`lengthl from an initial radius vec- LAR-S GSTAF NILSON. tor drawn normal to said curve, to the radius Witnesses: -vector 180 removed therefrom. H. C. KARLsoN,

Signed. at' the borough of Manhattan, W. H. GEF.. 

